In lane, always make sure there’s a minion between you and him at all times to make it really difficult for him to land his Q.
When playing as a ranged champion, try and abuse your auto attack range to poke him down and gain a health lead. Do not over-commit to poking though.
If you’re playing as a utility Support, try taking Relic Shield instead of Spelltheif’s Edge to make the laning phase safer.
Avoid fighting or staying close to your teammates (bundled together). As Nautilus’s R can knock players up who come into contact with it, if you’re close to the focused ally you might get hit too.
Nautilus will often be the frontliner for his team. Once he has gone in, try to focus him down if his teammates do not follow him in. Naut struggles getting out again once going in- so if he makes a mistake, abuse it
Nautilus will auto attack anybody who comes close to him in attempts to CC them with his Passive. Try and stay away and out of range during team fights if you’re squishy.
Nautilus is strong at levels 1-3 and can play aggressive and look for kills with his Q. Ensure you’re always behind a minion whenever his Q is up to reduce his ability to kill you in lane.
As soon as Nautilus hits level 6 and unlocks his Ultimate R, his kill pressure will increase again and he can lock you down as soon as you overextend. Play less aggressive when his Ultimate R is up.
Nautilus spikes once he has Mobility Boots as it will help him roam really easily. Ping as soon as he goes missing so your allies know he’s missing.